amuse/lib/dsp.c

125 lines
3.8 KiB
C

#include "amuse/dsp.h"
static const int32_t NibbleToInt[16] = {0,1,2,3,4,5,6,7,-8,-7,-6,-5,-4,-3,-2,-1};
unsigned DSPDecompressFrameRanged(int16_t* out, const uint8_t* in,
const int16_t coefs[8][2], int16_t* prev1, int16_t* prev2,
unsigned firstSample, unsigned lastSample)
{
uint8_t cIdx = (in[0]>>4) & 0xf;
int32_t factor1 = coefs[cIdx][0];
int32_t factor2 = coefs[cIdx][1];
uint8_t exp = in[0] & 0xf;
unsigned ret = 0;
for (int s=firstSample ; s<14 && s<lastSample ; ++s)
{
int32_t sampleData = (s&1)?
NibbleToInt[(in[s/2+1])&0xf]:
NibbleToInt[(in[s/2+1]>>4)&0xf];
sampleData <<= exp;
sampleData <<= 11;
sampleData += 1024;
sampleData +=
factor1 * ((int32_t)(*prev1)) +
factor2 * ((int32_t)(*prev2));
sampleData >>= 11;
sampleData = DSPSampClamp(sampleData);
*out++ = sampleData;
*prev2 = *prev1;
*prev1 = sampleData;
++ret;
}
return ret;
}
unsigned DSPDecompressFrame(int16_t* out, const uint8_t* in,
const int16_t coefs[8][2], int16_t* prev1, int16_t* prev2,
unsigned lastSample)
{
uint8_t cIdx = (in[0]>>4) & 0xf;
int32_t factor1 = coefs[cIdx][0];
int32_t factor2 = coefs[cIdx][1];
uint8_t exp = in[0] & 0xf;
unsigned ret = 0;
for (int s=0 ; s<14 && s<lastSample ; ++s)
{
int32_t sampleData = (s&1)?
NibbleToInt[(in[s/2+1])&0xf]:
NibbleToInt[(in[s/2+1]>>4)&0xf];
sampleData <<= exp;
sampleData <<= 11;
sampleData += 1024;
sampleData +=
factor1 * ((int32_t)(*prev1)) +
factor2 * ((int32_t)(*prev2));
sampleData >>= 11;
sampleData = DSPSampClamp(sampleData);
out[s] = sampleData;
*prev2 = *prev1;
*prev1 = sampleData;
++ret;
}
return ret;
}
unsigned DSPDecompressFrameStereoStride(int16_t* out, const uint8_t* in,
const int16_t coefs[8][2], int16_t* prev1, int16_t* prev2,
unsigned lastSample)
{
uint32_t cIdx = (in[0]>>4) & 0xf;
int32_t factor1 = coefs[cIdx][0];
int32_t factor2 = coefs[cIdx][1];
uint32_t exp = in[0] & 0xf;
unsigned ret = 0;
for (int s=0 ; s<14 && s<lastSample ; ++s)
{
int sampleData = (s&1)?
NibbleToInt[(in[s/2+1])&0xf]:
NibbleToInt[(in[s/2+1]>>4)&0xf];
sampleData <<= exp;
sampleData <<= 11;
sampleData += 1024;
sampleData +=
factor1 * ((int32_t)(*prev1)) +
factor2 * ((int32_t)(*prev2));
sampleData >>= 11;
sampleData = DSPSampClamp(sampleData);
out[s*2] = sampleData;
*prev2 = *prev1;
*prev1 = sampleData;
++ret;
}
return ret;
}
unsigned DSPDecompressFrameStereoDupe(int16_t* out, const uint8_t* in,
const int16_t coefs[8][2], int16_t* prev1, int16_t* prev2,
unsigned lastSample)
{
uint8_t cIdx = (in[0]>>4) & 0xf;
int32_t factor1 = coefs[cIdx][0];
int32_t factor2 = coefs[cIdx][1];
uint8_t exp = in[0] & 0xf;
unsigned ret = 0;
for (int s=0 ; s<14 && s<lastSample ; ++s)
{
int sampleData = (s&1)?
NibbleToInt[(in[s/2+1])&0xf]:
NibbleToInt[(in[s/2+1]>>4)&0xf];
sampleData <<= exp;
sampleData <<= 11;
sampleData += 1024;
sampleData +=
factor1 * ((int32_t)(*prev1)) +
factor2 * ((int32_t)(*prev2));
sampleData >>= 11;
sampleData = DSPSampClamp(sampleData);
out[s*2] = sampleData;
out[s*2+1] = sampleData;
*prev2 = *prev1;
*prev1 = sampleData;
++ret;
}
return ret;
}